1. Field of the Invention
Embodiments of the invention relate to alarm systems and associated methods for protecting residences, businesses and other premises. More particularly, the present invention relates to a system and method for the detection of alarm conditions and operation of a local alarm as appropriate as well as communications between the protected premises and a central station. According to one aspect, different types of alarm conditions are distinguished in an alarm system controller by whether or not two way voice communications will be attempted to follow an alarm report.
2. Discussion of Related Art
Automated home and business alarm systems, sometimes termed “security systems” or “alarm systems,” comprise sensors that detect hazardous or potentially hazardous conditions at a monitored premises. In addition, control circuits are also employed that produce audible and/or visible alarm signals as warnings, and advantageously report the occurrence of alarm conditions by automated signals sent to a remote security service or authority who may respond to such signals. Among other possible alarm conditions are unauthorized entry or the unexpected presence of a person who may be an intruder, fire, smoke, toxic gas, high/low temperature conditions (e.g., freezing), basement flooding, power failure, etc. The alarm can concern any detectable condition that might lead to personal hazard or property damage. In a dire situation, an automated call for help might be directed to police or fire authorities. A typical automated message is directed to a remote security service, who may simply record the incident or may have a duty to contact a person at the premises or a person identified as associated with the account, in order to follow up with action as necessary.
Alarm systems typically comprise a plurality of sensors coupled by wired or wireless signal paths to controllers or control circuits that include a processor and programming stored in memory. The programming may support a selection of configuration options by way of switches, preliminary programming selections and the like. Sensor inputs typically are discerned by the type of parameter sensed, the location of the sensor, etc. In addition to autonomous sensors, a manually operated switch input may be provided, for example in the case of a wireless medical monitor worn by a person who uses a switch on a portable wireless unit to trigger a home alarm system, or in the case of a system having a “panic button” switch for signaling. By programming, the processor can be configured to respond to different sensed or switched alarm conditions in different ways.
One way that security systems protect persons and property is by generation of an alarm signal to announce a detected alarm condition. Alarm signals might be produced by operating a horn, siren, flashing light, etc. For some alarm conditions, an audible and/or visible alarm is appropriate, for example in the case of fire. For other alarm conditions, such as intrusion detection in an unoccupied premises, a silent signal sent to summon assistance may be more useful and appropriate. When a premises is unoccupied, and sometimes even when occupied, an alarm that locally announces an alarm condition is not sufficient. What is needed is to summon appropriate assistance or attention. Therefore, remote signaling capabilities are advantageous. The signaling may be programmable, for example, to select where an alarm report signal is to be sent. It might be desirable to send an alarm reporting message to the local police in the event of intrusion detection, to the local fire company in the case of a detected fire, or to an emergency service in the event of a medical emergency.
It is advantageous in addition to reporting an alarm condition that may require response by emergency services, to enable communications with persons at premises that may be occupied. Such communications may provide information that enables emergency responders to plan their response, to bring appropriate manpower and equipment as necessary. However, false alarms can occur. For example, residents sometimes fail to disarm an intruder detection sensor when moving about, entering or exiting a building with an armed security system. Voice communications are advantageous to confirm that the case is not a false alarm, to enable the security agent to determine whether the resident is under immediate threat, perhaps to prompt for assurances by asking for a security password.
A typical alarm system has sensors distributed around a premises, some associated with doors or windows, others with passageways and still others with discrete spaces such as rooms or levels (floors). The sensors can be coupled to the control circuits by wire connections or by wireless electromagnetic, optical or acoustic signal paths. Upon occurrence of a sensed parameter associated with an alarm condition, a sensor provides a signal to a controller that may be disposed at an alarm control panel. The sensor signal may derive from a switch closure or digital level or edge that is arranged to signal or trigger the controller. Alternatively, a sensor could provide an analog voltage level to a threshold detector at the controller. The sensors are either wired to discrete inputs of the controller or in a network arrangement have associated identification codes that are enrolled in the data memory of the controller, in either case to enable the individual sensor signals to be correctly interpreted, i.e., distinguished from one another so that an appropriate response is taken in view of the nature of the hazard.
When reporting the occurrence of an alarm condition to the authorities or to a security agency, it is necessary for the signal contents or the manner in which the signal is sent (e.g., the telephone number or network address to which the message is sent) to distinguish the premises that was the source of the alarm and preferably the nature of the alarm and perhaps other pertinent information such as the location of the sensor that detected alarm conditions. Conventionally, remote reporting of alarm conditions and also follow-up voice conversations to confirm or investigate and alarm, have been conducted using the public switched telephone network (PSTN). Such reporting is vulnerable to loss of connection.
In connection with unauthorized entry, a burglar or the like might sever telephone wires in an effort to disable reporting. In the event of fire or disaster, the public telephone network may not be operational. An alarm system is disclosed in US publication 2008/0240372, wherein an alternative communications path is provided over a cellular telephone network. The disclosed technique employs a programmed selection routine and a communications path selector. If the public telephone network is operational, reporting signals are sent over the public telephone network. Signaling over audio paths can comprise automated connection to a preprogrammed signal destination number, and signaling over the audio channel using a dual tone multifrequency (DTMF) decoder/driver or a frequency shift keyed modem. In any event, the signal alerts the central station to the alarm, at least identifies the source premises and may carry additional information. It is incumbent on the personnel at the security agency or central station to initiate voice communications with the monitored premises in order to verify the alarm condition or otherwise to communicate with persons who answer the phone at the monitored premises. In the referenced publication, the communications path selector can adapt when the public telephone network (PSTN) is inoperative. In that case (for example upon failure to detect a dial tone), the program can switch over to a cellular telephone network (GSM for Groupe Spécial Mobile) to attempt the call to signal the central station.
According to the communication technique in publication 2008/0240372 a GSM cellular transceiver is needed for wireless communications to a cellular telephone facility within range, such as a cell phone tower. If a transceiver is provided and coupled in data communications with the alarm system, (e.g., in association with the control panel) the referenced publication discloses a bridge system whereby calls that are initiated at one or more telephone sets on the premises, which calls normally would have been coupled to the public telephone network (PSTN), are coupled instead to the cellular transceiver that is provided for the alarm system. In this manner, calls of a general nature (not limited to alarm calls) can be made over the cellular GSM network when the public telephone network (PSTN) is inoperable.
The GSM network is useful as an alternative voice communication pathway for use when the PSTN is unavailable. The GSM protocol is one of digital communications and packet data switching. Audio voice signals are digitized, numerically compressed and sent and received using a radio frequency modem. A GSM system may have an associated General Packet Radio Service core network (GPRS), by which Internet packet data traffic likewise can be handled as TCP/IP traffic. A GSM system supports short message service (SMS), also known as text messaging.
It is useful that the GSM network can be exploited as a backup communication network, used for reporting alarms and also for general purpose when the PSTN is inoperable. However, cellular communications are more expensive than public telephone network (PSTN) calls. Both PSTN and GSM calls generally include associated encoded information identifying the calling party via a subscriber identity code (typically provided from a SIM or subscriber identity module). What would be advantageous is a way to optimize the integration of GSM, SMS, GPRS and cellular communications capabilities with an alarm panel and communication arrangement for a security alarm system. According to the present disclosure, techniques are provided to exploit the available communication paths, and not merely GSM and PSTN voice communication pathways, in ways that take advantage of the digital signaling and analog voice communications that are called for in alarm system communications, with respect to operability, speed, cost and functional effectiveness.